How to store the pgm file open into buffer using "strcat"

[Silentkiller]

Hi,
I need some help with storing the Data of Pgm file into Buffer using Strcat;
Here is my source code:

/* fread example: read a complete file */
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

int main () {
FILE * pFile;
long lSize;
char * buffer;
char filename[80];
int ch;
int type;
int i;
printf(&quot;Please enter the file name : &quot;
scanf(&quot;%s&quot;, &filename);

pFile = fopen (filename, &quot;r&quot; );
if (pFile==NULL) exit (1);


ch = getc(pFile);
if (ch != 'P')
{
printf(&quot;ERROR(1) : Not Valid PGM File type\n&quot;
exit(1);
}

printf(&quot;\n The filename is %s&quot;, filename);

ch = getc(pFile);
type = ch - 48;
if (( type != 2) && ( type != 5))
{
printf(&quot;EORROR(2): Not Valid PGM File type\n&quot;
}

printf(&quot;\n The value is %ld\n&quot;, type);

// obtain file size.
fseek (pFile , 0 , SEEK_END);
lSize = ftell (pFile);
rewind (pFile);

// allocate memory to contain the whole file.
buffer = (char*) malloc (lSize);
if (buffer == NULL) exit (2);

printf(&quot;\n The Filesize = %ld\n &quot;, lSize);
// copy the file into the buffer.
for (i=0; i<lSize; i++)
{
strcat(buffer, filename);
}
/*** the whole file is loaded in the buffer. ***/

// terminate
fclose (pFile);

return 0;
}

your help will be greatly appreciated

 

[StevieK]

PGM - portable graymap file format (apparently).

Anyway, it really doesn't matter what type of file it is... If you just want to put the whole thing into a string using stream I/O routines, you can do it like this...

  rewind (pFile);

  // allocate memory to contain the whole file.
  buffer = (char*) malloc (lSize+1);
  if (buffer == NULL){
    printf("Error: Not Enough memory.\n");
    exit (1);
  }

  // The source and destination strings for

strcat()

  // must be null-terminated, so we do this to

buffer

  // and the same for

readCharacter

  buffer[0] = 0;

  char readCharacter[2];  // Latest read character
  readCharacter[1]= 0;    // .. and a NULL character

  // Now add characters to the string until
  // the end of the file is reached

  while(!feof( pFile ))
  {
    readCharacter[0] = getc(pFile);
    strcat(buffer, readCharacter);
  }

  // Close the file
  fclose (pFile);

  // ...
  //  Do interesting stuff with the

buffer

 string
  // ...

  // Free the allocated memory for

buffer

  free(buffer);

Hope it helps you,
Stephen